Lubrication system for rack and pinion mast

ABSTRACT

A lubrication system for a rack and pinion mast of a drilling rig includes a lubricating pinion positioned on a cart and in engagement with the rack. The lubricating pinion includes a plurality of lubrication dispensing ports formed on faces of the teeth of the pinion. The lubrication dispensing ports are fluidly coupled to lubrication ports formed in the lubricating pinion. The lubrication ports fluidly couple to an inner bore of the lubricating pinion. The inner bore may be fluidly coupled to a lubricant reservoir.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a nonprovisional application that claims priorityfrom U.S. provisional application No. 62/341,117, filed May 25, 2016.

TECHNICAL FIELD/FIELD OF THE DISCLOSURE

The present disclosure relates in general to drilling rigs, and inparticular to a drilling rig employing a carriage movable along racks.

BACKGROUND OF THE DISCLOSURE

Drilling rigs typically include one or more hoisting apparatuses. Insome drilling rigs, the hoisting apparatus may be a carriage movablealong a vertical mast. The carriage may include one or more motors whichturn pinions in engagement with racks positioned on the mast to move thecarriage vertically.

SUMMARY

An embodiment of the present disclosure is directed to a lubricationsystem for a carriage movable along a mast having a rack. Thelubrication system includes a lubricating pinion, the lubricating pinionmechanically coupled to the carriage and in engagement with the rack.The lubricating pinion includes a lubricant dispensing port. Thelubricant dispensing port is formed on a face of a tooth of thelubricating pinion. The lubrication system also includes a lubricantreservoir and a pump to pump lubricant from the lubricant reservoir tothe lubricant dispensing port.

Another embodiment of the present disclosure is directed to a method.The method includes providing a mast, the mast having a rack. The methodalso includes mechanically coupling a carriage to the mast such that thecarriage is movable relative to the mast. The carriage includes alubrication system. The lubrication system includes a lubricatingpinion, the lubricating pinion mechanically coupled to the carriage andin engagement with the rack. The lubricating pinion includes a lubricantdispensing port, the lubricant dispensing port formed on a face of atooth of the lubricating pinion. The lubrication system also includes alubricant reservoir and a pump to pump lubricant from the lubricantreservoir to the lubricant dispensing port. The method includes pumpinglubricant from the lubricant reservoir to the lubricating pinion anddispensing lubricant from the lubricant dispensing port.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is best understood from the following detaileddescription when read with the accompanying figures. It is emphasizedthat, in accordance with the standard practice in the industry, variousfeatures are not drawn to scale. In fact, the dimensions of the variousfeatures may be arbitrarily increased or reduced for clarity ofdiscussion.

FIG. 1 depicts a lubrication system consistent with at least oneembodiment of the present disclosure.

FIG. 2 depicts a schematic view of a lubrication system consistent withat least one embodiment of the present disclosure

FIG. 3 depicts a perspective view of a lubricating pinion used in alubrication system consistent with at least one embodiment of thepresent disclosure.

FIG. 4 depicts a cross section view of the lubricating pinion of FIG. 2.

FIG. 5 depicts a cross section view of the lubricating pinion of FIG. 2.

DETAILED DESCRIPTION

It is to be understood that the following disclosure provides manydifferent embodiments, or examples, for implementing different featuresof various embodiments. Specific examples of components and arrangementsare described below to simplify the present disclosure. These are, ofcourse, merely examples and are not intended to be limiting. Inaddition, the present disclosure may repeat reference numerals and/orletters in the various examples. This repetition is for the purpose ofsimplicity and clarity and does not in itself dictate a relationshipbetween the various embodiments and/or configurations discussed.

As depicted in FIG. 1, drilling rig 10 may include mast 15. Mast 15 mayinclude racks 20 mechanically coupled thereto. Carriage 25 may includeone or more drive pinions that engage with racks 20. The drive pinionsmay be powered by one or more motors including, for example and withoutlimitation, electric or hydraulic motors. Rotation of the drive pistonsmay cause carriage 25 to move vertically along mast 15. Carriage 25 maybe mechanically coupled to mast 15 in any suitable way known in the artwithout deviating from the scope of this disclosure.

In some embodiments, carriage 25 may include lubrication system 100.Lubrication system 100 may include one or more lubricating pinions 101.Lubricating pinions 101 engaged with racks 20 such that lubricatingpinions 101 rotate as carriage 25 moves vertically along mast 15.Lubricating pinions 101 may, as discussed further herein below, dispensegrease or other lubricant onto racks 20.

In some embodiments, as depicted in FIG. 2, lubrication system 100 mayinclude pump 103. Pump 103 may pump lubricant 105 from lubricantreservoir 107 through lubricant supply line 109 to manifold 111. Pump103 may be a rotary driven hydraulic pump, reciprocating piston pump,or, as would be appreciated by one having ordinary skill in the art withthe benefit of this disclosure, any pump capable of pumping the selectedlubricant 105 through lubrication system 100. Lubricant 105 may in someembodiments be grease. In some embodiments, manifold 111 may couplelubricant supply line 109 to lubricating pinions 101 via pinion supplylines 113, allowing flow of lubricant 105 to lubricating pinions 101. Insome embodiments, one or more valves 112 may be positioned betweenmanifold 111 and pinion supply lines 113, allowing flow of lubricant 105to lubricating pinions 101 to be regulated as discussed further hereinbelow. In some embodiments, valves 112 may be controlled by controller115. In some embodiments, valves 112 may be, for example and withoutlimitation, ejectors. In some embodiments, controller 115 may controlpump 103 to regulate flow of lubricant 105 to lubricating pinions 101.In some embodiments, controller 115 may control the flow of lubricant105 by turning on or off pump 103. In some embodiments, controller 115may control a pumping rate of pump 103. In some embodiments, controller115 may open or close valves 112 to permit or restrict flow of lubricant105. In some embodiments, controller 115 may partially open valves 112to control the flow rate of lubricant 105. In some embodiments,controller 115 may be controlled or adjusted remotely, such as, forexample and without limitation, from a drill chair.

In some embodiments, lubrication system 100 may provide a continuousflow of lubricant 105 to lubricating pinions 101. In some embodiments, adiscontinuous flow of lubricant 105 may be supplied to lubricatingpinions 101. For example and without limitation, lubricant 105 may besupplied to lubricating pinions 101 at a preset interval or in responseto operator input. In some embodiments, controller 115 may regulate thesupply of lubricant 105 to lubricating pinions 101 based on operationsof drilling rig 10. For example, in some embodiments, lubricant 105 maybe supplied to lubricating pinions 101 when carriage 25 is in motion. Insome embodiments, lubricant 105 may be supplied to lubricating pinions101 when carriage 25 is moving downward, moving upward, or when carriage25 is moving either downward or upward.

In some embodiments, as depicted in FIG. 3, each lubricating pinion 101may be mechanically coupled to frame 117. Frame 117 may mechanicallycouple to carriage 25 to support lubricating pinion 101 in engagementwith rack 20.

In some embodiments, each lubricating pinion 101 may include one or morelubricant dispensing ports 119. Lubricant dispensing ports 119 may beformed on teeth 121 of lubricating pinion 101. In some embodiments, oneor more lubricant dispensing ports 119 may be formed on each face 123 ofeach tooth 121. Lubricant dispensing ports 119 may be positioned onteeth 121 along the path of contact between teeth 121 and rack 20. Insome embodiments, lubricant dispensing ports 119 may be positioned alongthe pitch circle of lubricating pinion 101. Pitch circle, as understoodin the art, signifies the imaginary circle of lubricating pinion 101which would rotate without slip as lubricating pinion 101 moves alongrack 20.

In some embodiments, as depicted in FIG. 4, each lubricant dispensingport 119 may be fluidly coupled to a respective lubricant port 125. Eachlubricant port 125 may extend radially inward toward inner hub 127 oflubricating pinion 101.

In some embodiments, with reference to FIGS. 4, 5, inner hub 127 mayinclude inner bore 129. Inner bore 129 may be fluidly coupled to pinionsupply line 113. In some embodiments, inner bore 129 may be in fluidcommunication with lubricant reservoir 107 when lubricant 105 issupplied to lubricating pinion 101. In some embodiments, inner bore 129may be fluidly coupled to lubricant fitting 131. In some embodiments,inner hub 127 of lubricating pinion 101 may remain stationary withrespect to frame 117. In some such embodiments, teeth 121 may be formedon pinion outer body 133 which may rotate freely relative to inner hub127. In some embodiments, one or more bearings 135 may be positionedbetween inner hub 127 and pinion outer body 133.

In some embodiments, inner hub 127 may include radial dispensing port137. Radial dispensing port 137 may be fluidly coupled to inner bore 129and may radially extend from inner bore 129 to an outer surface of innerhub 127. Radial dispensing port 137 may be oriented such that as pinionouter body 133 is rotated, a lubricant port 125 may come into alignmentwith radial dispensing port 137, allowing fluid communication betweeninner bore 129 and lubricant dispensing ports 119 coupled to thelubricant port 125. Radial dispensing port 137 may, in some embodiments,be oriented relative to carriage 25 such that lubricant 105 is dispensedby lubricant dispensing ports 119 when they are in a desired relativeorientation to rack 20. For example and without limitation, in someembodiments, radial dispensing port 137 may be formed such that radialdispensing port 137 extends in the direction of rack 20, such thatlubricant 105 is dispensed to lubricant port 125 associated withlubricant dispensing ports 119 of tooth 121 engaged with rack 20.

In some embodiments, one or more seals 139 may be positioned betweeninner hub 127 and pinion outer body 133 to, for example and withoutlimitation, reduce or restrict lubricant 105 from flowing to lubricantports 125 not aligned with radial dispensing port 137.

In some embodiments, pinion outer body 133 may be formed from one ormore subcomponents. For example and without limitation, in someembodiments, as depicted in FIG. 5, pinion outer body 133 may be formedfrom subcomponents core 141 and one or more spreaders 143. Core 141 may,in some embodiments, be formed from a rigid material and may houselubricant dispensing ports 119 and lubricant ports 125 as describedherein above. In some embodiments, core 141 may be formed from a rigidmaterial such as aluminum or steel. In some embodiments, spreaders 143may be formed from a conformable material such as rubber or foam.Spreaders 143 may, in some embodiments, spread lubricant 105 dispensedfrom lubricant dispensing ports 119 of core 141 across face 123 of tooth121. Although depicted as including a single core 141 and two spreaders143, one having ordinary skill in the art with the benefit of thisdisclosure will understand that any number of cores 141 and spreaders143 may be utilized in lubricating pinion 101.

The foregoing outlines features of several embodiments so that a personof ordinary skill in the art may better understand the aspects of thepresent disclosure. Such features may be replaced by any one of numerousequivalent alternatives, only some of which are disclosed herein. One ofordinary skill in the art should appreciate that they may readily usethe present disclosure as a basis for designing or modifying otherprocesses and structures for carrying out the same purposes and/orachieving the same advantages of the embodiments introduced herein. Oneof ordinary skill in the art should also realize that such equivalentconstructions do not depart from the spirit and scope of the presentdisclosure and that they may make various changes, substitutions, andalterations herein without departing from the spirit and scope of thepresent disclosure.

1. A lubrication system for a carriage movable along a mast having arack comprising: a lubricating pinion, the lubricating pinionmechanically coupled to the carriage and in engagement with the rack,the lubricating pinion including a lubricant dispensing port, thelubricant dispensing port formed on a face of a tooth of the lubricatingpinion; a lubricant reservoir; and a pump to pump lubricant from thelubricant reservoir to the lubricant dispensing port.
 2. The lubricationsystem of claim 1, wherein the lubricant dispensing port is fluidlycoupled to a lubricant port formed in the lubricating pinion.
 3. Thelubrication system of claim 2, wherein the lubricating pinion furthercomprises: an inner hub, the inner hub including an inner bore in fluidcommunication with the lubricant reservoir and a radial dispensing portextending from the inner bore to an outer surface of the inner hub; anda pinion outer body, the pinion outer body including the tooth, thelubricant dispensing port, and the lubricant port, the pinion outer bodyrotatable relative to the inner hub such that when the lubricant port isaligned with the radial dispensing port, the lubricant dispensing portis in fluid communication with the inner bore.
 4. The lubrication systemof claim 1, wherein the lubricating pinion further comprises a core anda spreader, wherein the lubricant dispensing port is formed in the core.5. The lubrication system of claim 4, wherein the core is formed from arigid material.
 6. The lubrication system of claim 5, wherein the coreis formed from aluminum or steel.
 7. The lubrication system of claim 4,wherein the spreader is formed from a compliant material.
 8. Thelubrication system of claim 7, wherein the spreader is formed fromrubber or foam.
 9. The lubrication system of claim 1, further comprisinga valve between the pump and the lubricating pinion.
 10. The lubricationsystem of claim 9, further comprising a controller to control the valve.11. The lubrication system of claim 1, wherein the lubricating pistoncomprises a plurality of lubricant dispensing ports formed on aplurality of teeth.
 12. A method comprising: providing a mast, the masthaving a rack; mechanically coupling a carriage to the mast such thatthe carriage is movable relative to the mast, the carriage including alubrication system, the lubrication system including: a lubricatingpinion, the lubricating pinion mechanically coupled to the carriage andin engagement with the rack, the lubricating pinion including alubricant dispensing port, the lubricant dispensing port formed on aface of a tooth of the lubricating pinion; a lubricant reservoir; and apump to pump lubricant from the lubricant reservoir to the lubricantdispensing port; pumping lubricant from the lubricant reservoir to thelubricating pinion; and dispensing lubricant from the lubricantdispensing port.
 13. The method of claim 12, further comprising: movingthe carriage relative to the mast; and rotating the pinion.
 14. Themethod of claim 13, wherein the lubricating pinion further comprises: aninner hub, the inner hub including an inner bore in fluid communicationwith the lubricant reservoir and a radial dispensing port extending fromthe inner bore to an outer surface of the inner hub; and a pinion outerbody, the pinion outer body including the tooth, the lubricantdispensing port, and a lubricant port fluidly coupled to the lubricantdispensing port; wherein the method further comprises: rotating thepinion until the lubricant port is aligned with the radial dispensingport; and supplying lubricant to the lubricant dispensing port.
 15. Themethod of claim 14, wherein the radial dispensing port is formed in thedirection of the rack.
 16. The method of claim 14, wherein thelubricating pinion further comprises a second lubricant dispensing portpositioned on a second tooth of the pinion outer body, the secondlubricant dispensing port fluidly coupled to a second lubricant port,and the method further comprises: rotating the lubricating pinion untilthe second lubricant port is not aligned with the radial dispensingport.
 17. The method of claim 13, wherein the lubricating pinion furthercomprises a core and a spreader, wherein the lubricant dispensing portis formed in the core, and the method further comprises spreading thelubricant with the spreader as the lubricating pinion is rotated. 18.The method of claim 13, wherein lubricant is dispensed when the carriageis moving one or both of downward and upward.
 19. The method of claim12, wherein the lubrication system further comprises a controller, andthe method further comprises controlling or adjusting the amount oflubricant dispensed with the controller.
 20. The method of claim 19,further comprising controlling or adjusting the amount of lubricantdispensed from a remote location.